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UNITED STATES PATENT @Erica STEPHEN S. HOE, OF TARRYTOVN, NEV YORK.

ELEcTRoTYPE-PLATE.

SPECIFICATION forming part of Letters'atent No. 286,821,` dated October 16, 1883.

- Application tied May/'16, lass.

T0 all whom it may concern:

Beit known that I, STEPHEN S. Hon, a citizen of the United States, residingin the city of Tarrytown, county of Westch ester, and State of New York, have invented certain new and useful ImprovementsY in Electrotype-Plates, fully described and represented in the following specification and the accompanying drawings, forming a part of the same.

It is well known to those familiar with the art of printing from electrotype-plates that before such plates can be used it is necessary to provide them with a backing of type or other similar metal; and also that, owing to the frail nature of these plates and their consequent liability to become cracked or distorted if bent after the backing is applied, it is necessary in preparing these plates for use upon a rotary printing mechanism to bend them to iit the curvature of the printing-cylinder before the backing is applied. In practice, however, it has been found very difficult to accomplish this bending in so accuratea manner as to produce a plate of regular and uniform curvature.

It is also well known to those familiar with the art of electrotyping that the weakest parts of these plates are upon the lines of the column-rules, and that in handling or bending these 'plates prior `to the application of the backing they are very liable to become broken on these lines, and thereby damaged'or en- It is the object of the present invention to obviate these difficulties and to these ends the invention consists in the method of backing electrotype-plates, which will be hereinafter fully explained and particularly pointed out.

In the accompanying drawings, Figure lis a plan view of the back of an electrotype-plate for one page of a three-column paper or magazine. Fig. 2 is a cross-section ofthe same upon an enlarged scale taken between two lines of words. Figs. 3, 4, and 5 are like views, illustrating the several operations involved in fitting the plate for use upon a printing-cylinder; and Fig. 6 illustrates a modification to be referred to.

Referring to said figures, it is to be understood that a represents an ordinary electro- (No model.)

ness, and then bent so as to fit the curvature of the printing-cylinder, it will be very liable to be ruptured or distorted so as-to be worthless, which fact, as before sta-ted, makes it necessary to give to the` plate the proper curvature before the backing is applied. On the other hand, it is very difficult to bend the plate to the proper shape at this stage-rst, because of its liability to break upon the column-rules, and, second, because its exceeding thinness and the irregularity of its surface render it almost impossible to make it assume an even curvature. The first of these difficulties is overcome in the present invention by filling or partially filling the channels at the back of the column-rules with lines d (see Fig. 3) of tin, solder, or typ'e-metal, which so strengthens the plate that it can be handled without danger of cracking or breaking. These lines will also give s uch a degree of rigidity to the plate that in many eases it can be successfully bent to the proper curvature to receive the proper backing. In most cases, however, it will be found preferable, while the plate is 4still in its flat condition, to not only fill the said channels, but to also cover its entire back with a thin coating, e, (see Fig. 4,) of tin or type-metal. `The lines d and coating e may in such case be applied togetheigvas indicated in- Fig. 6, or separately, as indicated in Fig. 4. This coating will give to the platea sufcient degree ofrigidity, so that it can be bent to and will retain a uniform and even curvature while the main backing is being applied, and yet will not, owing to its thinness, cause the plate to break or become distorted in the process of bending. After the thin coating e has been applied the plate will be bent to the proper curvature'in the usual manner, 'and will then receive the usual backing, g, as shown in Fig.

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5, after which it Will be ready to be placed covering the entire back of the plate with a upon the printing-cylinder. thin coating of tin or similar metal previous Vhat I claim isf Yto the application of the backing, all substan- 15 l. That improvement in the art of backing tially as described. 5 electrotype-plates which consists in provid- In testimony whereof I have hereunto set my ing` the channels at the back of the coluninhand in the presence of two subscribing Witrules with lines of tin or similar metal previ-A nesses.

ous to the application of the backing, all substantially as described. STEPHEN S' HOE' 1o 2. That improvement in the art of backing Witnesses:

electrotype-plates which consists in filling the JAS. A. HOVEY7 channels at the back of the column-rules7 and T. H. PALMER. 

